Recently, functions corresponding to the rearview mirror of a vehicle are being realized by a monitoring system made up of an image capture device and a display device. With a viewing method using a rearview mirror, a driver is able to move the range that may be viewed (hereinafter designated the “visible range”) by moving his or her head, eye position, or the like (hereinafter simply designated the “head position”). However, with a monitoring system that simply displays an image acquired with an image capture device on a display device, the visible range is fixed, and the driver is unable to move the range that may be viewed, even if the driver moves his or her head position. For this reason, Patent Literature 1 discloses the moving of the visible range according to a change in head position by detecting a change in the head position of the driver, trimming an image from a captured image of the surrounding area according to the change in the head position, and displaying the trimmed image on a display device.